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    • #68310
      Herbc
      Participant

      the 10+ ft inflatable with inflat floor will not get replaced right away, will try to watch for a craigslist RIB. But the engine situation has to be addressed and am agonizing over the heavy 9.9hp 4strokes. at around 90lbs.

      is that going to be to heavy for the pushpit and can anyone comment on planing with smaller units.

      To me the ship to shore transport is one of the most important aspects of cruising, so its time to make it good.

    • #77022
      john stevenson
      Participant

      Of course planning characteristics depend as much on the load in the dinghy
      as the power on the transom. With my 250 Lbs and a 9.9 on the transom of my
      10′ AB RIB I can plane fairly quickly. With another 150 Lbs on board it
      requires laying out over the bow to get it on a plane and a long run. I
      usually don’t bother. So IMO anything less than 9.9 is at best marginal for
      planning with any kind of load. Then again why do you need a planning
      dinghy? In Caribbean anchorages that probably is handy. Most other places
      you’re often anchored less than 1/4 nm from a beach or dock. So maybe a 5-8
      hp OB with another inflatable floor dinghy is the best option.
      I can wrestle my 9.9 2-stroke on and off the dinghy, but it is an effort.
      If I had a 4-stroke, I’m sure I would have to use a block and tackle.
      The reason I have a RIB and a 9.9 has nothing to do with cruising. It was
      to remain competitive in the dinghy wars when weekend sailing on the
      Chesapeake before I retired. Since then I’ve rarely had the boat on a
      plane.

      Regards,
      John Stevenson
      http://www.svsarah.com

      On Sat, Apr 16, 2011 at 8:09 PM, Herbc wrote:

      the 10+ ft inflatable with inflat floor will not get replaced right away,
      will try to watch for a craigslist RIB. But the engine situation has to be
      addressed and am agonizing over the heavy 9.9hp 4strokes. at around 90lbs.

      is that going to be to heavy for the pushpit and can anyone comment on
      planing with smaller units.

      To me the ship to shore transport is one of the most important aspects of
      cruising, so its time to make it good.

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      https://pearson424.org/mailman/listinfo/maillist_pearson424.org

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    • #77027
      quent
      Participant

      I agree with John. We have a 10′ Caribe RIB and a 15 hp 2 stroke Yamaha. Engine is same weight as a 9.9, and is still available new. We use a block and tackle hoist to move the engine buy I’m sure we’d do that with a smaller engine too. The dinghy is rated for up to 20 hp, but evrn 15 is overkill. We need at least two people to keep it on the water at full throttle.
      It was nice in the Abacos for snorkling trips, or inter-island but unless you actually want a powerboat, it is a lot of weight to drag around on a sailboat.
      Quent
      Clairebuoyant #132

    • #77028
      Anonymous

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    • #77029
      unabated
      Participant

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    • #77031
      Anonymous

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    • #77032
      madsailor
      Moderator

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    • #77033
      Anonymous

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    • #77037
      RichCarter
      Participant

      All the engine weight is normally on one davit. That puts about 150 lbs on one unless you take the engine off, quite a pain in the ass. The pushpit won’t handle that much weight. I tow my dinghy backwards with the transom on the davits and the bow in the water. Our dinghy is bigger than what you are considering but the technique still works for smaller boats. Someone makes a setup designed for towing this way.

      Rich

      On Apr 16, 2011, at 8:09 PM, “Herbc” wrote:

      the 10+ ft inflatable with inflat floor will not get replaced right away, will try to watch for a craigslist RIB. But the engine situation has to be addressed and am agonizing over the heavy 9.9hp 4strokes. at around 90lbs.

      is that going to be to heavy for the pushpit and can anyone comment on planing with smaller units.

      To me the ship to shore transport is one of the most important aspects of cruising, so its time to make it good.

      _______________________________________________
      maillist mailing list

      https://pearson424.org/mailman/listinfo/maillist_pearson424.org

      _______________________________________________
      maillist mailing list

      https://pearson424.org/mailman/listinfo/maillist_pearson424.org

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    • #77038
      Herbc
      Participant

      does anyone have experience with these catamaran dinghys. logically the 2 hull design should go faster with a smaller engine.

      http://www.amiboats.com/boats/advanced.html

      of course there has to be a reason these aren’t on more boats, a bit heavy maybe.
      there is a dealer here in everett and i want to take a look, a demo would be great. this boat is sold under at least 3 different names, including Dux. But trying to see one is difficult till tomorrow.

    • #77039
      Anonymous

      FWIW.

      I have an avon 11 rib and a merc 9.9. The thing flies when its planing. Easy to get it up. Engine was lightest 9.9 at the time 2007. I raise the rib and engine on davits easily.

      Wavemaker


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    • #77040
      Phil Fontaine
      Participant

      While not as environmentally friendly, a 9.9 hp two stroke can save about 15
      pounds compared to a 90 lb four stroke. It is also worth noting that 9.9 hp
      engines are a creature of legal restrictions, mostly for use on inland
      lakes. Two stroke manufacturers typically serve this market by detuning
      engines capable of greater power. Most of the manufacturers offer the same
      basic engine at about 8 hp, 9.9 hp and 15 hp all weighing in at about 75
      lbs. The only differences being restrictions in the fuel system for the
      reduced hp versions and, of course, some difference in price. When
      considering those engines it is fairly easy to decide to take the 15
      providing one also selects a dinghy rated for that hp. As others have
      pointed out, one might not need a planing dinghy often but it sure is nice
      to have in certain cruising situations. A 10′ RIB with 15 hp will plain
      fairly easily with three adults and the difference in purchase price between
      8 and 15 hp sort of washes out over the years.

      My 10′ RIB weighs about 100 lbs and I carry it in davits with the 75 lb
      engine on and perhaps another 50-60 lbs of fuel, oars and anchor for typical
      coastal cruising.. I have Kato Marine davits rated at 300 lbs per arm. I did
      find that it was necessary to reinforce Aurora’s transom at the davit
      mounting points and also to add bracing to reduce the load on the stern
      rail. See Aurora’s davit bracing photo on the P-424 Gallery.
      Phil


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    • #77041
      joe shimkonis
      Participant

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      Joe Shimkonis

    • #77047
      RichCarter
      Participant

      I’ve heard that some folks have purchased the 9.9 engine and converted it to a 15hp engine by changing some jets in the carburetor, thereby saving a few bucks when purchasing. If you already have a 9.9, it might be worth looking into.

      Rich


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    • #77048
      john stevenson
      Participant

      I looked into that myself a number of years ago, when I was losing the
      dinghy wars to friends with 15s. The dealer said the modifications could be
      done by any decent engine shop, but I think he said it was more than just
      changing the carburetor. I decided not to try it, I had the 9.9 on a 70 Lb
      aluminum RIB, and that was scary enough for me.
      FWIW, you might be surprised at the actual HP on any give OB. I think the
      maximum shaft HP allowed for the OB to be classified as a 9.9 is 12 HP. The
      manufacturers sometimes try to cheat a little over the standardized values
      so that their owners could beat the owners of the other OBs.

      Regards,
      John Stevenson
      http://www.svsarah.com

      On Mon, Apr 18, 2011 at 3:55 PM, wrote:

      Quote:
      I’ve heard that some folks have purchased the 9.9 engine and converted it
      to a 15hp engine by changing some jets in the carburetor, thereby saving a
      few bucks when purchasing. If you already have a 9.9, it might be worth
      looking into.

      Rich


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    • #77049
      Anonymous

      I have a 4 stroke Suzuki and I was told the only difference between my 15 hp and
      a 9.9 is the throttle setting, mine being able to go to a higher RPM.
      The engine weighs 108 lbs , the same as a 9.9 because it is the same engine.
      I have a 10′ Avon RIB. I would only recommend my set up if you like to get to
      far away places  and want to be sure you can get back fast, if circumstances
      require.

      Joe,
      Half Moon ( and New Moon )

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    • #77050
      Anonymous

      My Merc 9.9 weighs a LOT less than 108.
      Sent from my BlackBerry® wireless handheld


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    • #77051
      unabated
      Participant

      The difference between the 9.9 and the15 is a plate under the carburetor. It’s like the restrictor plate used in NASCAR….Same carburetor used on both engines.
      alan

      — On Mon, 4/18/11, wrote:

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    • #77052
      RichCarter
      Participant

      I have a 9.9 Suzuki on a boat at our lake house. Very nice little engine.
      Starts with one pull and pushes our aluminum skiff just fine. Any more info
      on what I’d have to adjust?

      The engine on my dinghy is 30hp. I don’t think the boat could handle more
      so no need to screw with that. Planes fine with 6 people and can pull a
      water-skier, though not at the same time.

      Rich

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    • #77055
      Anonymous

      Rich,
      I don’t have first hand experience but I was told that the throttle mechanism
      has a regulator that keeps the RPM from reaching the potential. I don’t recall
      what the red line is on the Suzuki, but that regulator can be adjusted to raise
      the RPM to a level which makes the HP 15 rather than 9.9.

      We have a similar situation with the Yanmar where a 54HP engine can be put out
      70+ HP just by increasing maximum RPM from 3000 to 3600 ( and using a turbo
      charger). But it’s basically the same engine.

      I believe all 9.9 HP outboard engines are designed to achieve 15HP by increasing
      RPM some 20%.

      Joe,

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    • #77058
      sumocean
      Participant

      Someone said the the pushpit will not handle a 110 lb engine. What is the basis for this statement? I have a 15 hp Mercury that I got a deal on 10 years ago and it has sat in the barn till this year when I came across a used 10′ ABI RIB that is rated to 15 hp. I was hoping the 15 would be great for this set up. I know that I sit on and pull on the pushpit and I am topping 350 these days so I will need the 15 just to get my big ol’ butt on a plane. I made a lifting strap and was planning to use the mizzen sheet like Tor mentioned to aid in the lifting to the rack on the push pit. I made the outboard rack from a deck cut out from Sea Ox boats where I worked in college. It is 3/4 plyboard with 1/4 of glass on each side so I know that will take 110 lbs. So I guess to the point: Do you think that the push pit will not handle the weight of the engine? Maybe something on the toe rail to catch the skeg of the engine to add support from eblow?

      Thanks

      Linus

    • #77059
      RLeeds
      Participant

      I have a 112 pound 25hp two stroke mounted on the pushpit. It has been on
      for 15 years now with no problems. I placed the teak mount at the cross
      between where the rais and welded vertical stachion meet. 3 u-bolts hold
      the teak mount in place. I use a forspar rig to lower the engine onto the
      rib (12 ft Caribe).

      Rodd Leeds
      Windseeker


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    • #77061
      Hull152_Patrick
      Spectator

      I have an 80lb Yamaha F8 Fourstroke on my stern pulpit mounted as you
      mention. Pics and a write up on that here: http://deepplaya.com/?p=129

      If you want to do a similar project, note that the pulpit is curved..
      I didn’t account for that when I was building this at the shop and had to
      remove more material to make that “T” fit properly on the pulpit.

      -p

      —
      s/v Deep Playa | Pearson 424 Hull #152 | http://www.DeepPlaya.com | @DeepPlaya

      On Tue, Apr 19, 2011 at 11:44 AM, Rodd Leeds wrote:

      Quote:
      I have a 112 pound 25hp two stroke mounted on the pushpit. It has been on
      for 15 years now with no problems. I placed the teak mount at the cross
      between where the rais and welded vertical stachion meet. 3 u-bolts hold
      the teak mount in place. I use a forspar rig to lower the engine onto the
      rib (12 ft Caribe).

      Rodd Leeds
      Windseeker


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      Owners no more...
      Thanks Dawn and Patrick!

    • #77063
      RichCarter
      Participant

      I think I said it. My assumption was that there are davits attached to the push-pit and the weight is supported by the davits and push-pit. Maybe I misunderstood the question.

      If you’re just stowing the engine on the push-pit with no davits there is probably no practical limit. I went to Bermuda a few years back with my 30hp engine on the push-pit.

      Rich


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    • #77069
      Herbc
      Participant

      interesting to see all the combos, I really am a slo mo kinda guy and could get by with a none planning set up (read lite), but the other, better half feels the need for speed, who am I to argue.

      Stopped by and looked at the inflatable catamaran, they were closed but through the window I could see one up on its side, not much clearance, and really wide.

      Looks like for us a 9.9 merc and a rib 10 footer will be the way to go.

    • #77077
      sumocean
      Participant

      Thanks guys that makes me feel better. I was planning to use my 30 year old
      5 hp Yamaha this weekend till I have a chance to change the oils on the 15.
      Planning a short trip to the beach so no need for the big engine anyway. As
      luck would have it the Yamaha appears to have expired over the winter. To
      the marina I guess. 15 HP will be a priority now.

      Thanks

      Linus


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